Field of the Invention
The invention is generally directed to liquid formulations, or dry formulations that are readily solubilized in a fluid, that comprise metal oxide and/or metal hydroxide nanocrystalline particles. The formulations may be incorporated into fluid streams or applied to surfaces as in coatings or to treat gaseous and liquid phases. The formulations may also be used as a decontaminant for surfaces such as skin, clothing fabric, and other inanimate objects.
Description of the Prior Art
Nanocrystalline metal oxides and hydroxides have been shown to be useful as destructive adsorbents for various malodors and toxic materials, including acid gases, air pollutants, and chemical and biological warfare agents, due to their high surface reactivity (see e.g., U.S. Pat. Nos. 8,183,426, 8,038,935, 7,956,232, 7,566,393, 7,341,977, 7,335,808, 7,279,129, RE39,098, U.S. Pat. Nos. 6,887,302, 6,860,924, 6,827,766, 6,740,141, 6,653,519, 6,093,236, 6,057,488, and 5,990,373, each incorporated by reference herein in its entirety). Liquid formulations of metal oxides and hydroxides have been prepared in aqueous and non-aqueous solvents, along with polymers, surfactants, resins, and/or dispersing agents. However, the metal oxide and hydroxide particles have a tendency to agglomerate in solution. Additionally, it has proven difficult to achieve dry mixtures that are capable of producing stable and usable liquid formulations when added to liquid solution by the end user. Despite the prior work noted above, there is a need for stable, liquid formulations of a nanostructured (nanocrystalline) metal oxides and/or hydroxides, as well as for dry formulations that can be added to liquids at the point of use. Moreover, there is a need for fabric-type products and surface coatings that incorporate nanocrystalline metal oxide/hydroxide particles using stable liquid formulations.